source: ReferenceDesigns/w3_802.11/c/wlan_mac_high_framework/wlan_exp_ip_udp/wlan_exp_ip_udp_arp.h

/** @file  wlan_exp_ip_udp_arp.h
 *  @brief Mango wlan_exp IP/UDP Library (Internal Structures / Functions)
 *
 *  @copyright Copyright 2014-2019, Mango Communications. All rights reserved.
 *          Distributed under the Mango Reference Design license (https://mangocomm.com/802.11/license)
 */
#ifndef WLAN_EXP_IP_UDP_ARP_H_
#define WLAN_EXP_IP_UDP_ARP_H_

#include "wlan_mac_high_sw_config.h"

#if WLAN_SW_CONFIG_ENABLE_WLAN_EXP

#include "wlan_exp_ip_udp.h"

// Forward declarations
struct eth_rx_queue_buffer_t;
struct eth_tx_queue_buffer_t;

// ARP Table entry
typedef struct arp_cache_entry_t{
    u32 age;                 // Age that increments on receptions and is reset when a cache entry is confirmed
                             //  Since the cache size is limited, age is used to determine which entry should be
                             //  overwritten once the cache is full.
    u16 state;               // ARP_TABLE_USED or ARP_TABLE_UNUSED
    u8  haddr[ETH_ADDR_LEN]; // 6-byte MAC address
    u8  paddr[IP_ADDR_LEN];  // 4-byte IPv4 address
} arp_cache_entry_t;

void arp_init_cache();
int arp_process_packet(struct eth_rx_queue_buffer_t* eth_rx_queue_buffer, struct eth_tx_queue_buffer_t* eth_tx_queue_buffer);
int arp_update_cache(u8* hw_addr, u8* ip_addr);
int arp_get_hw_addr(u8* hw_addr, u8* ip_addr);

#endif //WLAN_SW_CONFIG_ENABLE_WLAN_EXP
#endif /* WLAN_EXP_IP_UDP_ARP_H_ */